The Analysis On LED Optical Mold’s Ultra-precision Machining Process

With the rapid development in LED industry, the need for the optical components which are used in the LED lights is more urgent. Injection molding is a good way to produce the optical components in a large scale. The LED optical components require the high accuracy in the surface and should be as smooth as a mirror. The quality of the optical component is up to the quality of the mold device, especially the optical mold core. So the assembly and manufacturing of the mold is the key to the quality of the optical components.In this paper, the technology about single point diamond turning (SPDT) has been discussed detailedly. We hope the technology about the single point diamond turning would be used for making the optical mold core. At first, this paper introduces the research status of the ultra-precision mold manufacturing and trends in this area. Secondly, some processes such as milling process, electrical discharge machining (EDM), wire cut Electrical Discharge Machining (WEDM) and grinding process which are used widely in mold industry has been discussed in detail from the view of process, and we provide some solutions to solve the problem which may occur in real production. At the same time, the principles about choosing mold materials are also have been pointed out.We discussed the theory about ultra-precision machining process by collecting a lot of papers about SPDT. We also explained the mechanism of micro-cutting, calculated the elastic refund (δ1) and get the formula of the minimum cutting thickness (apmin) with a certain tool edge radius (r). This paper point out that the precision of ultra-precision machine, cutting tool, process environment, quality of material, cutting data would make a difference on the component and the solving scheme is also put forward. This paper provides a reference to the SPDT.The structural characteristics of the optical mold core, accuracy, and surface roughness have been analyzed. Several current processes to making mold core have been compared, the advantages and disadvantages, applicable occasions also have been pointed out. At last, we decided to use the technology of SPDT to machine the optical mold core which is coated by the electroless nickel plating. Subsequently, the detailed description about processing of s electroless nickel plating, fixture design parts, and the impact of the tool setting on the part surface accuracy, cutting data, the way to blow Chip and Cooling also have been discussed.Using the software called UG NX (CAM) to make programs for mold machining parts. We can choose the suitable cutting data to machine the mold parts according to the results of the simulation in the computer. In this way, we can improve cutter pass. At last, we use UG to generate NC code for CNC machine.